These are legit offers from Marriott Vacation Club (MVC). I was also sceptical when I got the call but after a little bit of digging I decided to go for it.
Only catch is you and your spouse need to attend the 90 min presentation but remember to say "NO" at the end of it. That's all. The MVC team did mention that this packages and presentations are more prevalent in US/EU but now they are testing the Indian waters.
I was presented with packages of Nusa-Dua Bali / Phuket / Singapore and chose Singapore since they offered The Ritz Carlton for 2N/3D at 33k INR total (400 USD). Singapore hotels are usually pretty expensive and Ritz-Carlton regular nightly rate is >40k so their offer was a steal (33k for 2N!!!). More so because it's one of the handful of hotels that offers an unparalleled view of the Marina Bay.
I would say, if you get the offer, definitely go for it. Just remember to say "NO" at the end of the presentation 😀
These were the views from my room in Ritz-Carlton (went in May) -